Bounding in to fill a void that network television never allows to exist for more than five or six minutes at a time, ABC kicks off the May ratings "sweeps" tonight with the first half of "Lace II," a four-hour, two-part sequel to last year's trash smash about an illegitimate brat who becomes a porno star. You could call it fun junk, you could call it trippy pulp, but what you may want to do after about 30 minutes' exposure to it is just call it quits.

A meandering and self-congratulatorily low-minded continuation of the "Lace" yarn, "Lace II" is the kind of program that stumps hardened television critics constantly searching for ways to describe blithering idiocy. "Lace II" is idiocy at full and unfettered blither.

Airing tonight and Monday night at 9 on Channel 7, "Lace II" continues the saga of not-so-darling Lili (Phoebe Cates), the spiteful sprite who fought her way back from a commie prison camp so she could star in skin flicks and wreak retribution on humanity -- though in "II," a happier, if no less chubbier, face has been put upon her. At the midway point of "Lace," Lili had gathered together three women, all of them former classmates at a posh Swiss boarding school, so as to ask them the surly fade-out stumper, "Incidentally, which one of you bitches is my mother?"

That question having been answered, a new one is posed in "II." At the end of the first half tonight, li'l old Lil says to her mother's two former schoolmates, "I want you to help me find out which one of those bastards is my father. Help me find him, and he'll pay for what he did." We do find out in the final moments of the show, and he does pay.

The quest for papa's identity is set in motion by a farcically contrived plot twist. Lili's mother, Judy, played in the original by Bess Armstrong but played in the sequel by definitive ninny Deborah Raffin, is kidnaped by a tribe of guerrillas whose leader she intended to interview for her magazine. "I will diagnose the sickness of mankind," the leader promises her when she finally meets him, but he never even gets around to the subject of prime-time television. Having wandered off into the jungle alone in her peach fashion pants with $50,000 in cash to pay for the interview, and never dreaming skulduggery might be afoot, Judy is shocked to pieces to learn she is being held for ransom -- and a measly $1 million, at that, a figure that suggests the guerrillas' warlike ambitions are on the modest side. Maybe they planned to buy a dozen toilet seats from the Pentagon.

Lili, notified of the demands, decides her father, whoever he is, should ante up.

As clues to the father's identity, Lili and mom's old school chums consult a fancifully autobiographical romantic novel the mother had written years earlier. She called herself "Lucinda Lace" in the book and wrote three alternate versions of Chapter 12, the one in which Lili is conceived. So the three women track down the suspects based on the book's thinly veiled cues. One is an astronaut, one an orchestra conductor and the other an Arab king.

Lili herself tails the astronaut and confronts him in Paris in part two. At this point in the film she attempts to seduce a man she believes may well be her father, the new kink in titillation "Lace II" uses as a lure to viewers. "Do you want to go to bed with me?" she asks him. "Yeah, I do," he says. "How much?" she asks. "Very much," he says. "A million dollars much?" she asks.

When he tells her the price is a tad steep, Lili tells him he'll be getting a rare treat.

She, purringly: "After all, there is a special name for it."

He, eagerly: "What's the name?"

She, naughtily: "Incest."

We, wearily: "Oh, that."

Most of the rest of the core cast is back to reprise roles from the first "Lace," including Brooke Adams as Pagan (yes, Pagan), whose husband conveniently dies near the start of the film; Arielle Dombasle as Maxine, whose husband conveniently philanders off near the start of the film; and Anthony Higgins as Abdullah, the Arab king with the guilty conscience. An actor named Christopher Cazenove plays Raleigh, second in command to the rebel leader the heroine trots off to interview.

The one vaguely diverting touch to all this is that Judy's real life is supposed to be just as dizzily romantic an adventure as the book she wrote. She is swept off her feet by the handsome adventurer Raleigh there in the jungles of unidentified somewhere, east of the sun and west of Moon River. Or maybe knocked off her feet is a better way of putting it, because there's an ugly side to this tale. All three versions of Chapter 12 have Lucinda being taken against her will, even though she has made teasey seductive flirtations to the various aspiring takers. "Lace" abounds in rape fantasy, the kind of thing one might assume many women in the audience will feel insulted by. Although based on characters from a novel by Shirley Conran, the teleplay was written by a man, one Elliott Baker by name.

The director, Billy Hale, is quoted in TV Guide as having said, "I don't know what feminist groups would say, but I don't think they would have a lot of praise for 'Lace' to begin with. It's more like what Hollywood used to call a 'woman's picture.' " Women offered roles in "women's pictures" that perpetuate this kind of rape-me myth might want to think twice about accepting the jobs. The trouble with many actors is they are incapable of thinking even once.

As before, locations are exotic and eye-filling. In addition to Thailand, scenes were shot in France, Spain and the United Kingdom. The pity is that the splendiferousness is being used as a backdrop for the escape-fantasy equivalent of a stun gun. There's a lot of this kind of puerility on television, but much of it has more vulgar energy than "Lace II" does. The repetitious pop-"Rashomon" flashbacks keep dragging it to a halt, and there's never all that much to drag. After the fourth or fifth flashback to What Might Have Happened, even the most eager trash fanciers may find their interest expiring.

The big mystery of who fathered the girl turns out to be all quite arbitrary, without irony or reverberation. In addition, although "Lace II," like "Lace," has sex on the brain, almost all the sexual activity depicted is dark and joyless, an unpleasant chore for all concerned. For something the network tries to sell as "sizzling," hotsy-totsy stuff, "Lace II" turns out to be tediously coldsy-woldsy.